USN-8577-1: OpenSSH vulnerability
Publication date
21 July 2026
Overview
OpenSSH could allow unintended access to network services.
Releases
Packages
- openssh - secure shell (SSH) for secure access to remote machines
Details
USN-8222-1 fixed a vulnerability in OpenSSH. This update provides the
corresponding fix for Ubuntu 16.04 LTS.
Original advisory details:
Vladimir Tokarev discovered that OpenSSH incorrectly handled certificates
with the principal name containing a comma character when using user-trusted
CA keys in authorized_keys and an authorized_keys principals="" option
that lists more than one principal. This could result in inappropriate
principal matching, contrary to expectations. (CVE-2026-35414)
USN-8222-1 fixed a vulnerability in OpenSSH. This update provides the
corresponding fix for Ubuntu 16.04 LTS.
Original advisory details:
Vladimir Tokarev discovered that OpenSSH incorrectly handled certificates
with the principal name containing a comma character when using user-trusted
CA keys in authorized_keys and an authorized_keys principals="" option
that lists more than one principal. This could result in inappropriate
principal matching, contrary to expectations. (CVE-2026-35414)
Update instructions
In general, a standard system update will make all the necessary changes.
Learn more about how to get the fixes.The problem can be corrected by updating your system to the following package versions:
| Ubuntu Release | Package Version | ||
|---|---|---|---|
| 16.04 LTS xenial | openssh-server – 1:7.2p2-4ubuntu2.10+esm9 | ||
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